National Park The Old Post Office is one of the last remaining examples of Richardsonian Romanesque Architecture in Washington, D.C. The dominant park feature is the spectacular view from the 270-foot tower observation level, which is one of the best of the nation's capital.

National Historic Site Pennsylvania Avenue is certainly among the world's most famous streets. While the Avenue serves work-a-day Washington as a major east-west transit route, it is known the world over as the heart of the Nation's Capital.

National Memorial The Vietnam Veterans Memorial serves as a testament to the sacrifice of American military personnel during one of this nation's least popular wars. The memorial consists of three distinct sections.

Best Time to Visit District of Columbia

The best time to visit District of Columbia is in the summer and fall. Summer temperatures are mild with averages in the low 70's and highs in the mid 80's. Nights are cool with lows in the low 60's. Fall temperatures are cool with averages in the low 50's and highs in the low 60's. Fall nights are cold with lows in the low 40's.